Happy to report after a 260 mile round trip, I averaged 27.0 mpgs at an average speed of 68 mph. Our Impala SS used to average 23.6 for the same loop. I'm happy!

Saw a '10 Camaro in Comanche Texas, a red 1LT A6. It got me thinking what kind of mileage the '10s are getting? Anyone have any real world data?

 

Wow, that is fantastic. I'm surprised the Impala SS was that low. The 6 speed auto really does a good job.

 

15 to 16 city driving....

 

Yeah, the SS never got close to what the sticker said it would, unless you kept it at 55mph, but where can you do that anymore? In town, wifey would maybe get 14 out of it. So far, the G8 seems to get a couple more in both categories, which I'm really glad about because regardless of the sticker, I was going to be happy if it was just a wash w/ the SS. The fact that it has .7 liters more displacement and 60 more hp is all the more amazing. A6's rule I guess.

 

Best I've been able to squeeze out of our G8 is 23.7MPG highway. Loaded down with kids and clothes and other junk for the trip, but not shabby for a 6.0 V8 sedan.

Wish the AFM mode would stay engaged longer. In the future may opt for HP Tuners to see if we could enable the AFM mode to hold active over a larger parameter range.

 

Where do you see if the AFM is engaged or not?

 

Get into 'Engineering Mode' by holding down the left *** on the steering wheel while starting the car. So I've been told...

 

Best I've seen so far (~1,500 miles) is 21.3 mpg tank. That's comparable, on average, with the 2007 335i (~22 mpg avg) I had previously and a bit better than the 04 A4 GTO (~20 mpg avg) previous to that. Of course, the GTO improved about 10% after a semi-custom DiabloSport tune. That car, in both driveability and economy, was significantly improved with a tune. I just did a Superchips Cortex tune on my G8 yesterday; will be interesting to see if I get a comparible post-tune mileage improvement.

 

What grade gas are you running?

 

That blows away the 20mpg my Magnum is getting on highway trips. Normal driving with a 50-50 mix between city/hwy, I'm getting 16-17mpg. I've got a Superchips tuner as well (along with CAI and exhaust), and haven't played around with the extended fuel mileage setting. I've kept it on the 91 octane tune mostly.

 

There's a very slight vibration and audible change to the car when it goes to 4cyl mode. Seems at 45/50mph or so it's more noticeable than at 70mph.

We're running 87 octane since day one.

 

Damn, I can get 17.5 out of the '03 Suburban on the highway. Those sedans aren't much better.

 

It's very easy to make comparisons between city mileage numbers for cars vs hwy mileage numbers for trucks.

Easy, but totally irrelevant. But if it makes someone happy... why not?

 

27mpg is a lot better than 17.5, in fact it is 54% better.

 

I've got a Vector ECM and trans flash in my G8 GT and I'm averaging about 26-27 combined with a heavy foot and a trunk full of sales material.

I put on 1k miles on average/week and it's 2/3 hwy